<h3>如何设置一个在数组中循环的index</h3>
<article>
    arr = [1, 2, 3, 4, 5];<br>
    currentArrIndex = -1;<br>
    this.currentArrIndex = (this.currentArrIndex + 1) % this.arr.length;
</article>
<h3>把对象拆分成数组</h3>
<article>
    const foo =&#123;name:'a',age:20&#125;
    const arr = Object.entries(foo);
    arr = [[name,'a'],[age,20]];
</article>
<h3>把数组合并成对象</h3>
<article>
    const arr = [[name,'a'],[age,20]];
    const foo = Object.fromEntries(arr);
    foo = &#123;name:'a',age:20&#125;
</article>
